A capacitor is an element that may store electricity therein, and when a voltage is applied to the capacitor in a state in which two electrodes are disposed to face each other, the electricity is accumulated in the respective electrodes. In a case in which a direct current (DC) voltage is applied to the capacitor, a current flows in the capacitor while the electricity is accumulated, but when the accumulation of the electricity is completed, the current does not flow in the capacitor. Meanwhile, in a case in which an alternating current (AC) voltage is applied to the capacitor, an AC current continuously flows in the capacitor while polarities of the electrodes are alternated.
Such a capacitor may be divided into several kinds of capacitors such as an aluminum electrolytic capacitor in which electrodes are formed of aluminum and a thin oxide layer is disposed between the electrodes formed of aluminum, a tantalum capacitor in which tantalum is used as an electrode material, a ceramic capacitor in which a dielectric material having a high dielectric constant such as a barium titanate is used between electrodes, a multilayer ceramic capacitor (MLCC) in which ceramic having a high dielectric constant is used in a multilayer structure as a dielectric material provided between electrodes, a film capacitor in which a polystyrene film is used as a dielectric material provided between electrodes, and the like, depending on a kind of insulator provided between electrodes.
The multilayer ceramic capacitor has recently been used mainly in various fields such as a high frequency circuit, and the like, since it has excellent temperature characteristics and frequency characteristics and may be implemented at a small size.
A multilayer ceramic capacitor according to the related art includes a laminate formed by stacking a plurality of dielectric sheets and external electrodes formed on outer surfaces of the laminate and having different polarities, wherein internal electrodes alternately stacked in the laminate may be electrically connected to the respective external electrodes.
As the number of dielectric layers stacked in the multilayer ceramic capacitor is increased, steps due to thickness differences between the internal electrodes and the dielectric layers are increased. These steps cause warpage phenomena of end portions of the internal electrodes due to stretching of the dielectric layers in a transverse direction in a densifying process of compressing a body.
That is, the end portions of the internal electrodes are bent in order to fill the steps, and in margin portions, empty spaces due to the steps are removed by the depression of covers and a reduction in a margin width. The empty spaces due to the steps are removed, such that capacitance layers are also stretched by the reduced margin width. A break down voltage (BDV) of the multilayer ceramic capacitor and reliability of the multilayer ceramic capacitor such as withstand voltage characteristics, or the like, are reduced due to structurally irregular stretching of the internal electrodes as described above.
In order to prevent warpage of the end portions of the internal electrodes, a method of additionally printing separate dielectric layers or dummy electrode patterns in the margin portions has been developed. However, in this case, a separate process should be performed and productivity is thus low, it is difficult to accurately print the dielectric layers or the dummy electrode patterns in the margin portions, and it is difficult to completely prevent warpage of the end portions of the internal electrodes.